I was reading some really fine metric print! Could have been my eyes, or my metric to std. conversion At any rate, I haven't done the math but I think you would still end up with an acceptable shoulder?.....Rich

So Rich, how does my 7mm Malum look? Doable?

__________________
"I'm just a peckerwood who lives in the hills with too many guns..." - Bob Lee Swagger

Another one of my new designs that's destined to be a masterpiece... I call it, the 7mm Malum.

Nice looking cartridge. Some tips...

The taper is only .004 per inch which is probably lead to extraction issues. Ackley's tapers were in the .008-.009 per inch range.

It looks like you've blown out the web about .002 thou from spec. A lot of guys when they design a cartridge/reamer, will actually push the web in instead of out. This helps keep the primer pockets tight and longer brass life. Also, new brass from the factory will usually be 2-3 thou less than spec so designing your dies and reamer to this dimension is a good idea IMO.

My suggestion would be to go to a .520 web diameter and a .502 shoulder diameter.

I would also recommend sending your drawing to Dave Kiff at PTG and give him a call and talk through your idea with him before you lay out any $$$$. That will go a long way in getting this right the first time.

__________________
- Mark

You will never know how much it has cost my generation to preserve your freedom. I hope you make good use of it.
~ John Quincy Adams

What is the parent dimension at the body/shoulder jct. in thousandths? If your measurements are correct; yes its doable. Your overall case length will likely shrink up to .020" when fireforming though. Did you take that into account?.......rich

What is the parent dimension at the body/shoulder jct. in thousandths? If your measurements are correct; yes its doable. Your overall case length will likely shrink up to .020" when fireforming though. Did you take that into account?.......rich

The case OAL is the same as factory 8x68s, but I shrunk the neck up to .300" from the shoulder side, so I could create the false shoulder for blowing the walls out during fire-forming.

__________________
"I'm just a peckerwood who lives in the hills with too many guns..." - Bob Lee Swagger

The taper is only .004 per inch which is probably lead to extraction issues. Ackley's tapers were in the .008-.009 per inch range.

It looks like you've blown out the web about .002 thou from spec. A lot of guys when they design a cartridge/reamer, will actually push the web in instead of out. This helps keep the primer pockets tight and longer brass life. Also, new brass from the factory will usually be 2-3 thou less than spec so designing your dies and reamer to this dimension is a good idea IMO.

My suggestion would be to go to a .520 web diameter and a .502 shoulder diameter.

I would also recommend sending your drawing to Dave Kiff at PTG and give him a call and talk through your idea with him before you lay out any $$$$. That will go a long way in getting this right the first time.

My taper should be 0.010"... I will adjust the web down to .520", and adjust the taper accordingly. Thanks for that tip!

I will call Dave soon. I am really digging this design, and it's beltless and the brass is somewhat inexpensive...Especially compared to STW brass, which is rediculously expensive.

__________________
"I'm just a peckerwood who lives in the hills with too many guns..." - Bob Lee Swagger

My taper should be 0.010"... I will adjust the web down to .520", and adjust the taper accordingly. Thanks for that tip!

I will call Dave soon. I am really digging this design, and it's beltless and the brass is somewhat inexpensive...Especially compared to STW brass, which is rediculously expensive.

A taper of .011" from the web to the shoulder is fine for that case. That is about what I run and have no extraction problems. It helps keep the case from stretching as much as does the 40 degree shoulder. P.O. was a little conservative......rich